1. Field of the Invention
The present invention relates generally to network powering systems and methods and, more particularly, to an energy efficient sleep signature in power over Ethernet.
2. Introduction
Power over Ethernet (PoE) provides a framework for delivery of power from power sourcing equipment (PSE) to a powered device (PD) over Ethernet cabling. Various types of PDs exist, including voice over IP (VoIP) phones, wireless LAN access points, Bluetooth access points, network cameras, computing devices, etc.
In a PoE application such as that described in the IEEE 802.3af and 802.3 at (which are now part of the IEEE 802.3 revision and its amendments), a PSE can deliver power to a PD over multiple wire pairs. In accordance with IEEE 802.3af, a PSE can deliver up to 15.4 W of power to a single PD over two wire pairs. In accordance with IEEE 802.3 at, on the other hand, a PSE can deliver up to 30 W of power to a single PD over two wire pairs. Other proprietary solutions can potentially deliver higher or different levels of power to a PD. A PSE may also be configured to deliver power to a PD using four wire pairs.